Remodeling of Brown and White Adipose Tissue by NT-PGC-1α-Mediated Gene Regulation. Mus musculus

The β-adrenergic receptor signaling pathway is a major component of adaptive thermogenesis in brown and white adipose tissue during cold acclimation. The β-AR activation highly induces transcriptional coactivator PGC-1α and its splice variant N-terminal (NT)-PGC-1α, promoting the transcription program of mitochondrial biogenesis and thermogenesis. In the present study, we evaluated the role of NT-PGC-1α in brown adipocyte energy metabolism by genome-wide profiling of NT-PGC-1α-responsive genes. Canonical pathway analysis revealed that a number of genes upregulated by NT-PGC-1α are highly enriched in mitochondrial pathways including fatty acid transport and β-oxidation, TCA cycle and electron transport system, thus reinforcing the crucial role of NT-PGC-1α in the enhancement of mitochondrial function. Moreover, gene expression profiling of NT-PGC-1α revealed activation of distinct metabolic pathways such as glucose, lipid and nucleotide metabolism and of signaling pathways such as RAR and PPAR-γ/RXRα activation in brown adipocytes. Together, our data strengthen our previous findings that NT-PGC-1α is a key regulator of mitochondrial oxidative metabolism and thermogenesis in brown adipocytes and further suggest that NT-PGC-1α influences a broader spectrum of thermogenic processes to meet cellular needs for adaptive thermogenesis. Overall design: Two samples from two groups: NT-PGC-1α overexpression and empty vector. There are technical replicates (A and B) for each group. Two RNA samples were pooled for each group.